miR-130a在猪皮下脂肪细胞分化中的调节作用

为研究miR-130a对猪皮下脂肪细胞分化的影响及可能机制,本试验分离猪皮下脂肪前体细胞,诱导分化为成熟脂肪细胞,检测脂肪细胞分化过程中脂滴变化及miR-130a及其可能靶基因TNF-α和PPARγ的表达模式.同时合成miR-130a mimics及inhibitor对细胞进行转染,并以乱序序列作为阴性对照(NC).细胞转染24 h后进行诱导分化,连续诱导8 d,检测各处理细胞的聚脂情况及甘油三酯含量变化,荧光定量PCR检测脂肪细胞分化相关基因的表达变化.结果显示,猪皮下脂肪前体细胞分化过程中脂滴逐渐变大增多,miR-130a、TNF-α和PPARγ的表达模式具有一定的相似性.转染结果显示,相对于对照组,miR-130a mimics转染组细胞脂滴减少变小,甘油三酯含量降低(P0.05),脂肪细胞分化相关基因LPL、PPARγ、adiponectin、FASN和葡萄糖转运相关基因GLUT1,GLUT4以及JNK通路上的PDE3B的表达均比对照组显著下调(P0.01);而miR-130a inhibitor转染组细胞则脂滴增多,甘油三酯含量提高(P0.05),但大部分分化相关基因的表达与对照组无显著差异,提示miR-130a可能不只通过单一的靶基因影响脂肪细胞分化.其结果为后续深入研究miR-130a调节猪脂肪细胞分化的通路及机制奠定基础.

Effects of MiR-130a on Procine Adipocyte Differentiation

To investigate the regulatory effects and mechanism of miR-130a in the differentiation of porcine adipocyte, porcine pre adipocyte were separated and treated with insulin, dexamethasone, oleic acid and octanoic acid for eight days. The accumulation of lipid droplets and the expression profile of miR-130a and its potential target TNF-α and PPARγ were examined. The mimics or inhibitor of miR-130a were transfected at 24 hours prior to the eight-day induction. The lipid droplets and the amount of triglycerides (TG) were detected by oil red O and TG assays. The expressions of fatty synthesis associated genes were quantified by real-time PCR. The result showed similarity expression profiles of miR-130a, TNF-α and PPARγ. during adipocyte differentiation as the lipid droplets growing larger. Overexpression of miR 130a attenuated the accumulation of lipid droplets with the decrease of the triglycerides（P<0.05）and the expression of fatty differentiation associated genes LPL (lipoprotein lipase), PPARγ (proliferator-activated receptor-γ), adiponectin, FASN (fatty acid synthase), PDE3B (phospho-diesterase 3B), GLUT(glucose transporter)1, and GLUT4（P<0.01）. Inhibitor of miR-130a suppressed lipid droplets accumulation and increased the triglyceride levels（P<0.05）, however, most tested genes had no significantly change over the control group, suggesting that miR-130a was not the only effector for adipocyte differentiation.